Different foods have widely differing amounts of water within them. The foods that dehydrate best are the ones that have a lot of water to begin with. Obviously, water has no calories, and it means more weight to carry.

Chopped spinach, for example, has a lot of water. I can reduce a whole frozen package in the dehydrator by 10:1 on weight. What I get is some green chips that rehydrate well. So, the dehydrated chips have all of the calories that the whole package had to begin with.

Tomato paste will dehydrate very well, and if you spread it out right, you get a tomato leather. Ziploc bag it. I keep it refrigerated until time for the trip, and then it keeps OK from then on. It rehydrates easily in water or soup. No calories lost. Probably 5:1 weight reduction.

It is easy to buy instant rice, so you don't need to do your own. I cook quinoa and then dehydrate it, and it turns out very good. No calories lost.

You can air dehydrate cooked meat, but the results are mixed (at least for me). Rehydration can be problematic, and sometimes there is a texture problem. So, if I need much in the way of cooked meat for a long trip, I typically purchase more freeze dried.

So, let's say that you are doing a long trip, and you normally need 2 pounds of food per day. If you did a lot of dehydrated veggies and a little freeze dried meat, you can probably cut that down to 1 pound per day or less. Note that you may have to spend more time and fuel rehydrating it in camp, so the victory is not pure.

"Because of the necessary low fat and moisture content, jerky is high in protein. A 30 g (about 1 oz) portion of lean meat, for example, contains about 7 g of protein. By removing 15 g of water from the meat, the protein ratio is doubled to nearly 15 g of protein per 30 g portion. In some low moisture varieties, a 30 g serving will contain 21 grams of protein, and only one gram of fat. This leads to the high price of such brands of jerky, as it takes 90 g of 99% lean meat to generate that 30 gram serving."

Also don't forget that certain foods are better freeze dried or dehydrated or vice versa.For example, I love cooking up and drying jasmine rice and various pasta shapes - so that I can have more gourmet "instant" items.But say green peas and green beans....they suck dehydrated and are better when freeze dried.

Always consider how much you will really use the dehydrator before spending a lot - you might find it is cheaper to just buy online the veggies/fruits and meats ready to go.

And on weight? Yes, freeze dried is usually lighter - but - it is bulkier as the items don't shrink down like dehydrated.

I have to disagree on the peas and green beans comment that they "suck when dehydrated". It's all in the rehydration technique and time allotment - with that you can have them come out as nice as freeze-dried at about 1/4 of the cost. That said, if you are in a big hurry and expect them to rehydrate in under 15 mins then go with freeze-dried.

I don't know if this would be exactly right with a NESCO but we did make a chart - Fresh/Dry Equivalencies - that you might find helpful. It shows the amount of fresh food and what that equals if it's freeze-dried or dehydrated. So, 8oz of fresh cabbage equals 1 oz of dehydrated cabbage which is about 1/3 cup. This might vary slightly depending on the dehydrator that you're using but it should give you a good idea of what to expect.

"I've read through old posts and related websites and saw interesting recipes but can't see any calories / oz ratios.. or in the case of meat, protein / oz."

We've also made a downloadable Nutrition per Ounce spreadsheet that includes many common backpacking foods. It shows the nutritional content contained in just one ounce of each food item so that you can easily compare the different types of food.

Frankly I have better things to do with my time when backpacking than wait 30 minutes or more for green beans, green peas and sweet corn to rehydrate. For folks who want their meals ready in a realistic amount of time and who do it FBC style, this is where buying freeze dried veggies rock. (And are worth the cost - though honestly it isn't that pricey to buy FD veggies!)

The issue with them dehydrated versus FD is the "chewy" factor. If not soaked long enough they will not rehydrate enough. If a person has time to let them sit, yes they will come back most of the way - or if they are one pot cooking you can soak and then bring the veggies to a boil.

But personally I find the perfect texture of the FD veggies mentioned above to be better tasting, fresher tasting and as well a better mouth feel.

DW- I don't know that the brand of dehydrator makes any difference in how much the food weighs after drying.

here's an example of what you might expect chicken to weigh after drying. Last week I dried 6-12.5oz cans of chicken in waterweights are according to my scalescontents before draining off the water weighed 4lb 7oz total contents after draining water weighed 2lb 10oz after draining for 10 mincontents after drying 13.2oz

I once dehydrated a yummy chicken/rice casserole dish containing peas. Unfortunately, I didn't do a test run on it at home! I didn't just rehydrate it, I cooked it in the pot for 20 minutes! The rest of the dish was complete mush, but the peas were still the consistency of buckshot.

I use the "Just Tomatoes" brand FD veggies, but there are other firms that make them.

Some veggies, like chopped spinach, dehydrate just fine.

The real moral of the story is always to dehydrate a very small batch at first and test the rehydration process at home!